[adjective] [before noun; not gradable] [informal] - (used when you do not know how many things there are) being the most recent in a long seriesI glanced at my watch for the nth time that morning.Compare N (LETTER).To the nth degree means as much or as far as possible.We were questioned to the nth degree.She takes vegetarianism to the nth degree.
NTH
Meaning of NTH in English
Cambridge English vocab. Кембриджский английский словарь. 2012